Piston and cylinder system



Aug. 22, 1944. P. DESCOURTIS PISTON AND CYLINDER SYSTEM Fild A ril 2,1942 w n y E .e 5 J m 4 WW 1 n 1 x c o 3] IH f 6 fi w J W t r u M H r mmi W I4 I|| wllll w m 'J 7 M A m do p 2 2 x 3 6 5 6 MM7 4 PatentedAug.22, 1944 UNITED STATES I .;i 1Fi-Ce A PaulDescourtis, I aris France;vested intlie' Alien Property Custodian i Application April 2, 1942, .senaijnoe isz zs In France March. .29, .1941

practice than those used forthe same; purposeupto the present time.

' According to a feature. of the present invention,

in a system of the kind above-referred to, the distributing means aredivided-into at leasttwo sets capable each of separately ensuring theworking of the system, under similar or differentconditions,the shiftingfrom one to the other being obtained by a relativedisp1acement,'forinstance a rotation of'180" about their common axis, ofthe piston and cylinder with respect to each other.

Other features of the present. invention will result from the followingdetailed description of some specific embodiments thereof.

Preferred embodiments of the present invention will be hereinafterdescribed, with reference to the accompanying drawing,given merely byway of example, and in which:

'Fig. 1 is a'diagrammatic-axial sectional view of a piston and cylindersystem for a pump, made according to a first embodiment of the presentinvention;

Fig. 2 is a diagrammatic transverse section on the line IIII ofFiga'l;

- Fig.3 is aview, similar to Fig; 1, showing this system in a differentrelative postion of the elements thereof;

Fig. 4 is an'axial sectional view of a: system of the same kind madeaccording to 'another embodiment'of the invention;

I Fig. 5 is a perspective view correspondingzto Fig. 4;

6 showsthe development-ofthe e'dgesiof the'active surfaces of the'pistonof -Figs.=4"-and' 5; In the following detailed descriptiom it will besupposed that the invention is applied'to the construction of aninjection pump, of the monocylindric or poly-cylindric type; to be usedfor the feed of an internahcombustion engine. "This pump will further besupposedito be ofthe kind in which the'distributing means includeedgesor inclined surfaces, especially.onthe'i pistbm variation of v the pumpoutput ibeingoobtained; by a relative rotationbf the-piston and cylinderwith. respect to-each other soas to, modifythe time at which .theorifice. or orifices .coacting with these edges .or inclined surfacesare opened and closed.

vIn..-pa'rticular,-it should-be remembered that,

inv existing .pumps of this, kind, .the variation, of theroutput ofthepump-can be obtainedinthree different ways, towitpbyadvancing thebeginningofthe injection, or on ,thecontrary.by-postponing the end.thereof, or .againby simultaneously varyingthe beginning andthe end.

- .NoW, it is. knownthatsome-motors are-preferably controlled by.variations of the first,.ki;nd,. others .;by variations. of the I second.kind,. and others: by variations of the third kind.- .I'It is.therefore necessary=to,.provide different interchangeable .pistonscorresponding respectivelyito these solutions. 4 I 7 An important object .of .the present invention is to obviate .this drawback,- andtothis. effect, accordingto. a feature of the -invention,. thedistributing means .of .the. pum are .divided. into two or moredistinctlsets. capable .each of separately ensuring the. distributionaccording to the respective. types of variation of the .output abovementioned. Shifting. fromvone. operation. to. the othervis obtained byarelative displacement, for instance La rotation of given amplitude abouttheir common *aXiS, ofthe.cylindereandmiston. In order to carry out thismethod of-working, many specific embodiments -.may be provided bypersons .skilled, in the art, .especia1ly.-according asone or severalorifices are .used, according-to the particular. arrangement-thatiswchosen for the distributing edges or inclined surfaces, andaccordingto the value of the amplitude of rotation of the piston andcylinder, with respect: to each other, .thi s=.amplitude beingpreferably chosen equal to when two different conditionsofoperation are.to be obtained, asrit will behereinafter-supposed.

--According to the embodiment of Figs. 1-to-3, I imake use of two setsof d-istributionedges, superposedalong the same generatrixof the.piston, to Wit:

-.a.-:A- first-set constituted, on the one hand by the edge 2 ofthe-piston end face whichgin this example, is at right angles tothe;piston axis,and, on the other hand by anoblique edge 3 of-a notch 4provided-laterally in the peripheryoi the piston;

.51). A- second set constituted, on the-one-hand by an obligue-, edge 5;which in thiScCfiiSEniS parallel nected with the piston endcorresponding to the face of the piston which compresses the fluid, theconnecting passage being formed either in the lateral wall of the pistonor on the inside thereof, as shown by the drawing (Figs. 1 and 3.conduits I6. I6 I6 In cooperation with such a piston, I make us of acylinder 8 provided with two orifices 9 and I located on diametrallyopposed generatricesk" these orifices being spaced apart in the axialdirection of the piston and cylinder, in such manner that it is possibleto bring either one of them (9, located at the upper part of thecylinder) into coaction with the first set of edges 2 and 3', ortheithere Ill, located at the lower part of the cylinder) with thesecond set of edges 5 and 6. The pump i'urtherincludes: Onthe one hand acontrol device. for instance of the camtype, for impartin grectilinearrecip rocating displacements to the piston, and

Onthe'other hand, means for producing relativerotations of the cylinderand piston with respect toeach other about their common axis, so as topermit of varying the output of the pump by modification of the relativepositions of the inclined edgeswith respect toorifices 9 and I0; Such asystem can operate in two different ways, respectively illustratedbyFigs. 1 and 3. It. will be seen that, in one of these ways of working,,correspondingto Fig, 1, the beginning oi the in ection remainsinvariable since it takes place when edge 2 comes to cl ose orifice 9,that is to say always at the same time whatever be the angular positionof the piston with respect to the cylinder. As the end of the injectiontakes place when oblique edge 3 uncovers said orifice, that is to say ata time variable in accordance with said angular position,'the variationof outputof the pump is obtained. by varying thetime at whichtheendofthe injection takesplace. 9n the contrary with the other way ofworkthe twoorifices.

initial adjustment of each of the two working positions, this adjustmentproducing a modification of the injection timing.

Finally, it goes without saying that suitable feed conduits are providedfor supplying fuel to that of orifices 9 and In which is chosen.

In Figs. 1 to 3, which correspond to an embodiment in which the shiftingfrom one of the ways of operation to the other is obtained by a rotationof 180 of the cylinder, the feed is ensured through a single conduit ll,of suitable section for enablingit to coact as well with one --as withthe other of said orifices, but separately. If they shifting from oneoperation to the other is obtained by a rotation of the piston, I mayhave recourse to two conduits located at the level of I might also, inboth cases, have recourse to a conduit surrounding the cylinder.

ing, the pump, the beginning of the injectionis variable, whilethe endis fixedn In. order to ensure the relative rotation of 180? whichpermits'of passing fromone working position totheother, I act either onthe piston or on i yli d Forthi s'purpose, I will merely, in some cases,act directly andvmanually upon fthe parts in question-Q For instance ifit is desired to modify the working position of the 'cylinder I removesaid cylinder as it isicustomary to do when a part of the pump is to beexaminedorchanged, after which said cylinder is refitted in an angularposition at 180 from the preceding angular position.-

But it maybe advantageous, in some'cases, to provide means forcontrolling from a distance the working position ofithe parts inquestion, which permits, in particular, simultaneously to act'on thepistons or cylinders of several pump units.

'I hese means may have their elements at least partly in'coin'mon; with-'elements of the means rying the output of thepump. v I r V They'mightfurther'beused for adjusting the injection'timin gl Supposing forinstance that said meansact on" the cylinder; by turning the latterthrough an-angle' of 180", they might be made insuch manner-as to permit0i e fecting an Instead of making use of two orifices as shown by Figs.1 to 3, I may provide a single one, for instance by'placing the two setsof inclined edges in suitable angular relation to each other, as shownby Figs. 4 to 6.

According to'this embodiment, and supposing, for the sake ofexplanation, that the piston is divided into.two portions by an axialplane, I provide, one one side of this plane, edges 2 and 3 analogous tothose above describedwith reference to Figs. 1 to 3, with a notch 4analogous to that disclosed by said figures. On the other side of saidaxial plane, I provide, on the one hand, an upper oblique edge 5symmetrical to edge 3 with reference'to said plane, and which may becon-' stituted by a bevelled edge of the piston end, and, on'theotherhand, a lower edge 6, with a notch I, said .last mentioned edge andnotch being perpendicular to the axis of the piston.

--.It-.wi1l be"readily' understood that these two setsof edges cancoact, one or the other, with the same orifice 9, thus producing twodifferent waysof working as above explained.

. The switching from one to the other can take place, in this case also,either by acting on the piston (as shown by the drawing, orifice 9 beingin this disclosure fed through a lateral conduit I I) or by acting onthe cylinder.

Fig. 6 shows, for the sake of clarity, the development of thedistributing edges. These edges may, as in the case of Figs. 1 to 3,extend over angles a of the same order of magnitude as usually employed(say since, in each of the two working positions, there is a margin ofnearly 18091available for adjustment.

Anyway, whatever be the particular embodiment that is chosen, I obtain asystem the operation of which is'sufiiciently clear from'the precedingdescription to make it unnecessary to enter into further explanations.This system has, over similar systems, many advantages,

' among which the following may be cited:

. It permits of adapting the pumps to engines of different types; and

It necessitates no modification of existing pumps, with theexception ofthe piston, which is difierent.

I The invention further permits of prolonging the life of the piston. Asit is known, the piston wears particularly on those of its surfaceswhich coact with the corresponding feed orifice. Therefore, if thewearbecomes too great, it is possible, byturning the piston through anangle of to obtain its "operationalong zones which are notworn.Accordingly, the present invention appliesJto the'case in whichthe'piston is provided withtwo' sets of distribution edges adapted to'feoa t senaratelyeeither; with ,thezsam torificesor with; twrzdistinctaorificesx so: asttorpr duo :two

@waysvof; workina-tzeventwhenithese; tworwayszare similar or evenidentical.

1onthe::other;:hand,:;it; should be :we1l 1..under- .stoodthat, wheniitiis desired;toiobtain-;ozbyzmeans in the other greet) ithese" :sets maybe {of ;:any 1 shape and disposition asrnecessary. ;-For.:-instance, atleast one ofthemmay-havetwo oblique -edges, either, of: the sameinclination or: of different: in- "clinations, and even Ofiopposedinclinations.

It isithus possible; witlra single. type: offpi'ston, to iadaptzan given:pump to two wholly "'diiferent applications. I I :In ageneralmannen-whilezI-have, in theabove said-setofdistributin mea ibein indpend nt y adjustablezby relativerotation of said; pistonand cylinderabout: their: common axis.

description,xdisclosed-whati'lfdeem to be practical .and eflicientembodimentsrfofthe presentiinven-o .tion, it should be "wellunderstoodthat I do not wish ito-i be limited thereto as Ethere mightibe changesmade in the arrangement,idisposition and 'i-form of the parts awithoutdeparting 'from the principle. Qf'thes present invention:asEcomprehended :within theliscope :ofth appended claims. I I Intheclaims,sthe;.wordinner* applied to one of two elements designates theone which is nearer to the part of the cylinderttoward which K the"liquid is discharged underpressure. For instance, taking edges"3.1an'd'25,the finner" edge is =edge3'. y What-'I claim is:

1. A pump, which comprises; in combination,

a cylindenazpiston slidablei in said cylinder, one of these two parts'abeingi provided with-at least one port means connected= with a -fluidsupply, at least two independent sets-of distributing means carried bythe other of said'two parts, ia'dapted: to

cooperate with said port means, said piston and cylinder being rotatable'with respect to each sets of distributing means alternatively "-intofooeither of said sets 'of distributing -mean's alternatively into 7cooperating relation with said port means.

3. A pump, which comprises," in combination.

a cylinder, a piston slidable in said cylinderjone of -these two partsbeingprovidedfwith at least one port means connected with a fluidfsupplyat least two independent setsof distributing means carried by theother-fofsaid two parts',-adapte'd to cooperate with said portmean's,said pisto'n and cylinder being adjustable with respect {to each otherby relative rotation about-their common axis so --as I to 'permit ofbringing either of' s'aid sets of distributing-means' alternatively intofoo operating I relation with said I port rneansi each- 0f lar position'of'th'e I 4. 'A"pump,"which; comprisesrin combinatioma rcylinder :andipiston .i slidable in each other and angularly:adjustablewith' respectto each other about their. common :zaxis, said cylinder beingprovided-With; at least oneiport means connected with a: fluid supply;said piston being provided with anindependentrperipheral notch, with aconduit connecting said iinotch with said inner face of the piston, withat least one other independent peripheral? 'notchvand with a conduit.connecting said-second mentioned notch with said' inne'r face .of thepiston,'sai'd-notches being so located' that the :port means cooperatewith .the edge 0f the end' face of the piston and with the'inneredge ofthe first mentioned sl'oti'when the piston and 'cylinder are'in a givenrelative angular position with respect to each othenwhile 'the-portmeanscooper'atewith: an edge of the second-mentioned slot for another.relative angular position of "the piston and cylinder about their-commonaxis at least .one of the edges of the piston which c'ooperates with;the port means in each of-said angular positions being oblique withrespect to the axialdirection. I

5. A pump, which comprises, in combinationj 'a cylinder and pistonslid'able in each other and angularly adjustable with respect to eachother about their common axis, said cylinder being pro- 'vided withatleast one port means connected with a fluid supply, said piston beingprovided with an independent peripheral notch with at leastone otherindependent peripheralnotch a'ndwitha conduit connecting both of saidnotches With said inner facedf the piston, said notches being-solocated'that the port means cooperate I with I the edge of the endi'face of thepiston and with the inner edge of the first mentioned slot when thepiston and cylinder are in a given relativ angular position iWl'threspect toeach' other, whilefthe portme'ansicooperates with an edge ofthe second mentioned slot foranother relativeangular position of" thepistonfiand cylinder abouttheir-com-,

mon axis, at least one of the edges cf' the pi'ston which cooperateswith thefport means in each of said angular positions being oblique withrespect to the axial direction. 4 V I .fi'flApumnawhich comprises,ii-combination, a cylinderiiand piston slidable ineach other andan-gularly adjustable" with respect to each other about their.c'cnimonaxis, said cylinder'being providedwith at least one portmeans-connected with ia fluid -supply, said piston being provided with 13, peripheral notch with at least one other peripheral notch, 'and withla' conduit connecting both of said notches-With said inner 'face "ofthe pistonj. said' -cylinder -bing adapted to have said port meansconnected"with a fluid -supply,'-said notches' loeing sc -locatedthatthe port-means cooperate with the edge of the end face of the pistonand with the inner edge of jthe' first 'mentioned slot' whemthe pistonand cylinder arejin a give'n relative angular position with respeotttoeach other, while the 'port means cooperates with an edg e oftheseccndmentioned slot tor aid-angurelative position; at -least one I o co'nim nains at "from the "first m ntioned n' each other-aria piston an'dcylinder about their in-combination angularly adjustable with-respect toeach other abouttheir common axis,'said cylinder being provided with atleast'one port means connected with a fiuid supply, said pistonbeingprovided with an independent peripheralnotch with at leastone otherperipheral notch,'and with an axial'conduit connecting both of said"notches with said inner face of the piston, said notches being solocated that the port means cooperate with the edgeof thegendifaceof thepiston andwith the inner edge-of the first mentioned notch when thepiston and cylinder arein a given 'relative an'gu- -lar,;position':withrespect to each"other,while the port-,means cooperates with an edge ofthe second mentioned'notch for another relative "arig- :ular position'ofthe piston and cylinder about their common axis, at least oneo'f theedges of ;the piston which'c'ooperates with the port means in each of'said angular positions being oblique with respect to the axialdirection. a 8, A pump, which comprises, in combination,

a cylinder and pistonslidable in each other and angularly adjustablewithrespect to each other about. their common axis, said cylinderbeing'provided with two ports located on generatrices at 180 from eachother andat a distance from each other in the axial direction, saidpiston-being provided with a peripheral notch,'with a conduit connectingsaid notch with said inner face of the piston, with another peripheralnotch located substantially in line with the first inthe axialdirection,and with a conduit connecting said first mentioned notch and with theinner edge ofthe second mentioned notch for airelative angular positionof said piston and cylinder at 180 from the first'mentioned position, atleast oneof the edges adapted to cooperate with each port being obliquewith respect to the axial direction. I

. 9.v A'pump, which comprises, in combination, a cylinderand pistonslidable in each other and an- .gularly adjustable with respect to eachother about their common axis, said cylinder being provided with twoports located on generatrices at 180 from each other and at a distancefrom each other in the axial direction, said piston being provided witha peripheral notch, with an inner conduit extending therethrough andconnecting said notch with said inner face of the piston, with anotherperipheral notch located substantially-in line with the first in theaxial direction, and'with an inner conduit extending therethrough andconnecting said second mentioned notch withsaid inner face of thepiston, said cylinder being adapted to have either of said portsconnected with afluid supply, said two ports being so spaced apart,.inthe axial direction that one of them cooperates with the edge of the endface of the piston and with the inner edge of the first-mentioned notchwhen the piston and cylinder are in agiven relative angular positionwith respect position, atleast oneof the edges'adapted to coto eachotherwhile the other port cooperates with the other edge of said firstmentioned notch and with the inner edge of the second --rnent ioned QP rIF Fi iY a la Po i ive 9 a d-R g operate with each port being obliquewith 're'spect to the axial direction.

i v a J v10. A pump, which comprise'sjin combination, a cylinder andpiston'slidable in each other and angularly adjustable with respect toeach other about their common axis, said cylinder being provided withtwoiport means connected with'a fluid supply, said pistonlbeing providedwith an independent peripheral notch, with a conduit con 'necting saidnotch with: said inner face of the :piston, with" at least'f one otherindependent peripheral notch and with a conduit connecting "said secondmentioned: notch with said inner face of'the 'piston,rsaidnotches beingso located that" one port means'c'ooperates with the edge of the endface of the piston and with the 'inner'edge of the first mentioned slotWhenthe piston and cylinder arein agiven relative angular position withrespect to each other,'while the other port means cooperates with anedge of the second mentioned 'slot for'another relative angular positionof the piston and cylinder about their common'axis; at least-one ofthe'edges of the piston v which cooperates with the'port means in eachof said angular p'ositions being oblique withrespect to the aXl&1di1eCti0n.'Z"' Y 11. A pump, which comprises, in combination, a cylinderand piston slidable in .eachother and angularly adjustable'with respectto each other about their common axis, said cylinder being provided withtwo ports" located on generatrices at from each other and at 'a'distancefrom each other in the axial direction, said piston being provided witha peripheral notch, with another peripheral notch substantially in .line.withithe first notch, in the axial direction, and witha conduitconnecting both of saidnotc'hes withsaid inner face of the piston said"cylinder. being adapted to have eitherof? said' ports connected with afluid supply, said twoports being sozspaced apart, inthe axialdirection-that oneg of them cooperates with-the edge of the end face ofthe piston and with the inneredge'of the first men,- tioned notch when:the piston andicylinder are in a given relative angular position with'respect to each other whilethe otherport cooperates with the other'edgeof said first mentioned notch and with the inner edge of the,secondqmentioned notch for'a relative-angular position ofsaid piston andcylinder at 180 from the first mentioned position, at least one of theedges adapted to cooperate with each port being oblique with respectto-the axial direction. -1 2.' A pump, which comprises, in combination,a; cylinder and piston slidable in each-other and angularly adjustablewith respect ;to each other about their common axis saidcylinder beingproadded with two-ports locatedon generatrices at 180 from each otherandat a distancefromeach other in the axial direction said piston havingits inner end face located in a plane at right angles to its axis; andbeing provided with a peripheral notch both-:edges of which are obliquewith respect to the axial direction, with a conduit connecting saidnotch withsaid inner face of the piston, ,with another iperipheral notchhaving its inner edgeat right angles-to. the axis of'said piston,- andsubstantially in line with the first notch in the axial direction, andwith a conduit connecting said second-mentioned notch with said innerface of the piston, said-cylinder being adapted to have-either of saidports connected w h. a idupp v aidtwqz norts ng cp ed apart, in theaxial direction that one of them cooperates with the edge of the endface of the piston and with the inner edge of the first mentioned notchwhen the piston and cylinder are in a given relative angular positionwith respect to each other while the other port cooperates with theother edge of said first mentioned notch and with the inner edge of thesecond mentioned notch for a relative angular position of said pistonand cylinder at 180 from the first mentioned relative angular position.

13. A pump, which comprises, in combination, a cylinder and pistonslidable in each other and angularly adjustable with respect to eachother about their common axis said cylinder being provided with a portconnected with a fluid supply,

one side of said piston having its inner end face located in a plane atright angles to its axis and being provided with an independentperipheral notch the inner edge of which is oblique with respect to theaxial direction with a conduit connecting said notch with said innerface of the piston, the opposite side of said piston being provided witha peripheral portion oblique to the axial direction, and with anotherindependent lateral notch having its inner edge at right angles to theaxis of said piston, with a conduit connecting said second mentionednotch with said inner face of the piston, said piston being adapted tohave the set of edges, on either side thereof, brought into co-operatingrelation with said port, alternatively.

14. A pump, which comprises, in combination, a cylinder and pistonslidable in each other and angularly adjustable with respect to eachother about their common axis, said cylinder being provided with a portconnected with a fluid supply, one side of said piston having its innerend face located in a plane at right angles to its axis and beingprovided with an independent peripheral notch the inner edge of which isoblique with respect to the axial direction, the opposite side of saidpiston being provided with a peripheral portion oblique to the axialdirection and with another independent peripheral notch having its inneredge at right angles to the axis of said piston, with a conduitconnecting both of said notches with said inner face of the piston, saidpiston being adapted to have the set of edges, on either side thereof,brought into co-operating relation with said port, alternatively.

15. In a pump, the combination of a cylinder provided with inlet means,and a piston slidable and rotatable in said cylinder and having two setsof edges, the inner edge of one set and the outer edge of the other setbeing in planes at right angles to the longitudinal axis of the piston,and the outer edge of said first mentioned set and the inner edge ofsaid second mentioned set being in planes oblique to said axis, saidpiston being provided with a conduit having a port in the upper face ofthe piston and ports associated with each of said outer edgesrespectively, so that the edges of the respective sets will 00- operatewith said inlet means of the cylinder, alternatively, depending upon therelative angular positions of the cylinder and piston.

16. In a pump, the combination of a cylinder having two inlet ports, anda piston slidable and rotatable in said cylinder, and having two sets ofedgesythe inner edge of one set and the outer edge of the other setbeing in planes at right angles to the longitudinal axis of the piston,and the outer edge of said first mentioned set and the inner edge ofsaid second mentioned set being in planes oblique to said axis, saidpiston being provided with a conduit having a, port in the upper face ofthe piston and ports associated with each of said outer edgesrespectively, so that the edges of the respective sets will cooperatewith said cylinder ports respectively and alternatively, depending uponthe'relative angular position of the cylinder and piston.

17. In a pump, the combination of a cylinder having an inlet port, and apiston slidable and rotatable in said cylinder and having two sets ofedges, the sets being formed on diametrically opposed sides of thepiston, the inner edge of one set and the outer edge of the other setbeing in planes at right angles to the longitudinal-axis of the piston,and the outer edge of said first mentioned set and the inner edge ofsaid second mentioned set being in planes oblique to the said axis, saidpiston being provided with a conduit having a port in the upper face ofthe piston and ports associated with each of said outer edgesrespectively so that the edges of the respective sets will cooperatewith said cylinder port, alternatively, depending upon the relativeangular positions of the cylinder and piston.

PAUL DESCOURTIS.

